JP2001008892A - Light source device and endoscope system - Google Patents

Abstract

(57) [Problem] To provide a light source device which is excellent in monochromaticity and can be used easily, and an endoscope system provided with the light source device. SOLUTION: In a light source device 2 of an endoscope system for fluorescence observation, a light emitting element 21 (light emitting diode or laser diode) capable of emitting excitation light for exciting auto-fluorescence of living tissue is used as the light source. The light source device 21
A light emitting element mounting portion 22 having a concave surface 22a is formed, and a large number of light emitting elements 21 are fixed on the concave surface 22a.
The excitation light emitted from each light emitting element 21 is directed to the incident surface J of the light guide / fiber bundle 15b in the fiberscope 1 of the endoscope system. These excitation lights are
All are incident within the opening angle of the light guide 15b. The light guide 15b can guide a sufficient amount of excitation light having excellent monochromaticity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a light source device for making light incident on a fiber bundle and an endoscope system capable of observing an image of a subject inside a living body or the like.

[0002]

2. Description of the Related Art It has been known that autofluorescence emitted from abnormal living tissue due to a lesion or the like is weaker than autofluorescence emitted from normal living tissue. A fluorescence observation endoscope system that observes autofluorescence in a body cavity of a living body by utilizing the characteristics of the living tissue has been put to practical use.
This fluorescence observation endoscope system includes a fiberscope 1,
And a light source device 8 connected to the fiberscope 1.
And an imaging device 3. FIG. 4 is a schematic configuration diagram showing a conventional fluorescence observation endoscope system.

First, the fiberscope 1 will be described. The fiberscope 1 has an insertion portion 11 to be inserted into a living body, an operation portion 12 connected to the insertion portion 11, and a connection tube 13 connected to the operation portion 12. Insertion part 1
Three through-holes are opened in the distal end surface of the light-emitting device 1. One of these is used as a forceps hole 14a, and the other two are respectively provided with a light distribution lens 15a for illumination and an observation light distribution lens 15a. Is sealed by fitting the objective lens 16a.

The operating section 12 has one end connected to the proximal end of the insertion section 11 and an eyepiece optical system 16c inside.
Is arranged. Then, the insertion unit 11 and the operation unit 12
Inside, an image guide / fiber bundle 16b (hereinafter abbreviated as an image guide) is passed. This image guide 16b has its distal end face
6a and the base end face of the eyepiece optical system 1
6c.

The connecting tube 13 has one end connected to the side surface of the operation section 12 and the other end connected to the light source device 8. The light guide / fiber bundle 15 is inserted into the insertion section 11, the operation section 12, and the connecting pipe 13.
b (hereinafter abbreviated as light guide). The light guide 15b has an exit surface facing the light distribution lens 15a, and an end on the incident surface side is drawn into the light source device 8.

The light source device 8 includes a xenon lamp 81,
It has a reflecting mirror 82, an infrared cutoff filter 83, and a light source side bandpass filter 84. Xenon lamp 81
Can emit bright white light. Reflecting mirror 82
Is disposed at a position where the white light is reflected and converged on the incident surface of the light guide 15b. In addition, between the xenon lamp 81 and the reflecting mirror 82 and the light guide 15b, an infrared cutoff filter 83 that removes infrared rays in white light to prevent radiation of heat, and almost excitation light (wavelength band: about A light source side band-pass filter 84 that transmits only light having a wavelength of 400 nm to 450 nm) is provided.

Therefore, the light emitted from the xenon lamp 81 and condensed by the reflecting mirror 82 is transmitted to the infrared cutoff filter 83.
After the infrared rays are removed by the light source, the components in the wavelength band other than the excitation light are substantially blocked by the light source side band-pass filter 84, and the light enters the light guide 15b as excitation light from the incident surface of the light guide 15b. .

The excitation light guided inside the light guide 15b is emitted from the light exit surface of the light guide 15b and further diverged through the light distribution lens 15a. Then, the excitation light irradiates a body cavity wall as a subject to generate autofluorescence on the body cavity wall. The autofluorescence emitted from the body cavity wall enters the objective lens 16a together with the excitation light reflected on the body cavity wall surface. The objective lens 16 converges these lights on the distal end surface of the image guide 16b to form an image of the subject. The image guide 16b transmits this image to the eyepiece optical system 16c.

Next, the imaging device 3 will be described. This imaging device 3 is provided with an eyepiece optical system 16 c of the fiberscope 1.
And an optical path for guiding the light transmitted therethrough. Then, the imaging device 3 sequentially transmits the band pass filter 31, the condenser lens 32, and the image intensifier 3 on this optical path.
3, an imaging optical system 34 and a camera head 35 are provided.

The band-pass filter 31 blocks the excitation light and transmits only the auto-fluorescence. Condenser lens 32
Collects the auto-fluorescence transmitted through the band-pass filter 31 and makes it incident on the image intensifier 33.
The image intensifier 33 amplifies and emits incident light. The imaging optical system 34 converges the amplified light on the imaging surface of the camera head 35 to form an image of the subject. The camera head 35 converts the image on the imaging surface into an electric signal,
(Hereinafter abbreviated as CCU). The CCU 4 converts an electric signal obtained from the camera head 35 into a video signal and causes the monitor 5 to display the video signal.

The fluorescence observation endoscope system further includes a polychromator 6, and a personal computer 7 connected to the polychromator 6. The polychromator 6 has a light guide probe 6a, and can detect the intensity of light incident from the tip of the light guide probe 6a for each wavelength.

The light guide probe 6a is connected to the fiberscope 1
Is inserted through the forceps insertion opening 14b opened in the operation unit 12 of the first embodiment, is drawn through the inside of the fiber scope 1, and the distal end thereof comes out of the forceps opening 14 a of the insertion unit 11. The polychromator 6 detects the intensity of the autofluorescence guided by the light guide probe 6a for each wavelength, converts the intensity into a signal, and outputs the signal to the personal computer 7. The personal computer 7 causes the monitor 7a to display a graph showing the intensity distribution of the autofluorescence for each wavelength.

[0013]

According to the fluorescence observation endoscope system of the prior art having the above-described structure, the light source device 8 is provided.
Obtains excitation light by causing white light to enter the bandpass filter 84. However, at present, it is impossible for the band-pass filter 84 to completely block light outside the predetermined band that is originally desirable as excitation light. Therefore, light outside the predetermined band transmitted through the band-pass filter 84 may adversely affect observation.

Further, a laser light source device may be used instead of the light source device 8 described above. In this case, since the emitted laser light has excellent monochromaticity, it is not necessary to use the band-pass filter 84 or the like. However, in order to generate a laser beam with an amount of light required as excitation light, a large-sized device such as a gas laser light source device is required. Further, such a laser light source device requires a predetermined idling time before starting to use, so that it takes time to prepare in advance. Further, there is a problem that the initial cost and maintenance cost of the device are high.

An object of the present invention is to provide a light source device and an endoscope system which can emit light with excellent monochromaticity and can be used easily.

[0016]

SUMMARY OF THE INVENTION An endoscope apparatus according to the present invention employs the following configuration in order to solve the above-mentioned problems.

That is, the light source device according to the first aspect is a light source device that causes light to enter a fiber bundle from an incident surface thereof, and includes a plurality of light emitting elements capable of emitting light having directivity in a predetermined direction; The angle formed between the light beam emitted from each light emitting element and the central axis near the end on the incident surface side of the fiber bundle so that the light beam emitted from each light emitting element faces the incident surface of the fiber bundle. A light emitting element mounting portion for arranging the respective light emitting elements so as to be equal to or less than １ ／ of the opening angle of the fiber bundle.

With such a configuration, the light emitted from each light emitting element enters the incident surface of the fiber bundle within the conditions defined by the numerical aperture of the fiber bundle. Therefore, the light emitted from each light emitting element is all guided by the fiber bundle. The light emitting element is
They may be arranged according to a pattern such as hexagonal close-packed, square dense, or radial, or may be arranged randomly.

According to a second aspect of the present invention, in the first aspect, the light emitting element mounting portion has a concave surface facing the incident surface of the fiber bundle.
By being fixed on the concave surface of the light emitting element mounting portion,
It is specified. The shape of the concave surface may be a spherical surface, a paraboloid of revolution, or another aspherical surface. Further, the light emitting element may emit excitation light for exciting autofluorescence of the living tissue as monochromatic light.
Further, the light emitting element may be a light emitting diode or a laser diode.

According to a sixth aspect of the present invention, an endoscope system includes the light source device according to any one of the first to fifth aspects and a fiber bundle for guiding light emitted from the light emitting element of the light source device. An illumination optical system for emitting light guided by the fiber bundle to the subject, an objective optical system for converging light from the subject to form an image of the subject, and an objective optical system formed by the objective optical system Imaging means for imaging the image of the subject.

The endoscope system may irradiate the object with the light emitted from the light emitting element without passing through the fiber bundle. The display means is C
It may be configured by an RT, a liquid crystal display, a plasma display, or the like.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a fluorescence observation endoscope system according to an embodiment of the present invention will be described with reference to the drawings.

[First Embodiment] The fluorescence observation endoscope system according to the present embodiment includes a fiber scope 1, and a light source device 2 and an imaging device 3 connected to the fiber scope 1. FIG. 1 is a schematic configuration diagram illustrating a fluorescence observation endoscope system according to the first embodiment.

First, the fiberscope 1 will be described. The fiberscope 1 has an insertion portion 11 to be inserted into a living body, an operation portion 12 connected to the insertion portion 11, and a connection tube 13 connected to the operation portion 12. Insertion part 1
Reference numeral 1 denotes a flexible and substantially cylindrical shape having a distal end sealed with a disk-shaped distal end surface. And
At least three through-holes are opened in the distal end surface of the insertion portion 11, one of which is used as a forceps hole 14a, and the other two are respectively provided with a light distribution lens 1 for illumination.
5a and the objective lens 16a for observation are fitted and sealed.

The operation section 12 has one end connected to the base end of the insertion section 11, and a space communicated with the insertion section 11 is formed inside the operation section 12. The operation unit 12
An eyepiece optical system 16c is arranged on the other end side inside the camera. Various switches (not shown) for operating and setting the endoscope system are arranged on the surface of the operation unit 12.

In the insertion section 11 and the operation section 12, an image guide / fiber bundle 16b (hereinafter, referred to as "fiber bundle") is provided.
Image guide). This image guide 16b has its distal end face connected to the objective lens 16a.
And the base end face of the eyepiece optical system 16c
, And are arranged to face each other.

The objective lens 16a as an objective optical system is
The light emitted from the subject (body cavity wall) is transmitted to the image guide 16b.
To form an image of the subject. The light guided inside the image guide 16b is emitted from the base end face of the image guide 16b and travels to the eyepiece optical system 16c. The eyepiece optical system 16c can enlarge and observe the image of the subject.

A forceps insertion opening 14b is opened on a side surface near the distal end of the operation section 12. The forceps insertion opening 14b and the forceps hole 14a of the insertion section 11 are connected by a forceps tube (not shown). The forceps insertion port 1
Various instruments (forceps, treatment tools, probes, etc.) inserted from 4b are drawn through the forceps tube, and the tips of the instruments are put out to the forceps holes 14a.

The connecting tube 13 has flexibility, one end of which is connected to the side surface of the operation unit 12, and the other end of which is connected to the light source device 2. A light guide / fiber bundle 15b (hereinafter abbreviated as a light guide) is passed through the insertion section 11, the operation section 12, and the connection pipe 13. The ride guide 15b is configured by densely bundling a multi-mode optical fiber, and both end surfaces thereof are formed as an incident surface through which light enters and an exit surface through which light exits. And this light guide 1
The light-emitting lens 5b has a light-emitting surface facing the light distribution lens 15a, and an end on the light-entering surface side is led into the light source device 2.

As will be described later, the light source device 2
Causes excitation light of a predetermined wavelength that excites auto-fluorescence of living tissue to be incident on the incident surface of the light guide 15b. The excitation light guided by the light guide 15b is emitted from the emission surface of the light guide 15b, and is further diverged via the light distribution lens 15a to irradiate the body cavity wall as the subject. The light distribution lens 15a and the light guide 15b function as an illumination optical system.

Next, the imaging device 3 will be described. The imaging device 3 is provided with an operation unit 12 in the fiberscope 1.
Has an optical path in its housing, which is connected to the other end of the eyepiece and guides the light transmitted through the eyepiece optical system 16c. And
On this optical path, the imaging device 3 sequentially includes a bandpass filter 31, a condenser lens 32, an image intensifier 33, an imaging optical system 34, and a camera head 35.
Having.

The band-pass filter 31 transmits only the autofluorescence of the living body and blocks the excitation light that excites the autofluorescence. The condenser lens 32 condenses the light transmitted through the band-pass filter 31 and makes the light incident on the image intensifier 33. The image intensifier 33 amplifies and emits incident light. The imaging optical system 34 converges the light emitted from the image intensifier 33 on an imaging surface of a camera head 35 composed of a CCD, and forms an image of the subject.

The camera head 35 of the imaging device 3 is connected to a camera control unit 4 (hereinafter abbreviated as CCU). The CCU 4 is connected to a monitor 5 as display means. Then, the camera head 35 of the imaging device 3 converts the image on the imaging surface into an electric signal and transmits the electric signal to the CCU 4. This CCU 4 is a camera head 3
5 is converted into a video signal and displayed on the monitor 5.

The imaging device 3 has a sensitivity control section 36 disposed on the outer surface of the housing. The sensitivity control unit 36 is connected to the CCU via a cable.
4 is connected. By operating the sensitivity control unit 36, the surgeon can control the CCU 4 and adjust the brightness, contrast, and the like of the image displayed on the monitor 5.

It should be noted that the fiberscope 1 is
Is not connected, the image of the subject can be magnified by the eyepiece optical system 16c and observed by the operator under the condition that the subject is illuminated with white light.
However, in the present embodiment, the fiberscope 1
The eyepiece optical system 16c is connected to the image pickup device 3 so as to face the bandpass filter 31 of the image pickup device 3. In this state, the eyepiece optical system 16c of the fiberscope 1 relays the image of the subject to the camera head 35 together with the condenser lens 32 and the imaging optical system 34 of the imaging device 3.

Next, the light source device 2 will be described. The light source device 2 includes a plurality of light emitting elements 21 and a light emitting element mounting portion 2.
2 and a power supply 23. FIG. 2 is a diagram schematically showing the light emitting element 21 and the light emitting element mounting portion 22 of the light source device 2 together with the light guide 15b of the fiberscope 1. Hereinafter, FIG.

The light emitting element 21 is composed of a blue light emitting diode, and can emit monochromatic light having a wavelength of 450 nm or less with directivity, and the monochromatic light emitted from the light emitting element 21 functions as excitation light. Will be. The light emitting element 21 may be a laser diode capable of emitting a laser beam of a predetermined wavelength within a wavelength band capable of exciting auto-fluorescence.

The light emitting element mounting portion 22 has a substantially spherical concave surface 2.
2a. The light-emitting element mounting portion 22 adjusts the concave surface 22a of the light guide 15b so that the central axis of the concave surface 22a coincides with the central axis at the end of the light guide 15b of the fiberscope 1 on the incident surface J side. It is arranged so as to face the incident surface J.

Here, it is assumed that a predetermined cone extends toward the concave surface 22a with the center of the incident surface J of the light guide 15b as the vertex. This cone has the central axis of the concave surface 22a as an axis,
In addition, the angle (θ) between the axis of the cone and the generatrix is の of the opening angle (2θ) of the light guide 15b. That is, the sine (sin θ) of the angle (θ) between the axis and the generating line in this cone is the numerical aperture (NA) of the light guide 15b.
Matches. Then, each of the light emitting elements 21 causes the emitted excitation light to travel inside the cone to make the light guide 1.
The light-emitting element mounting portion 22
Is fixed on the concave surface 22a.

In FIGS. 1 and 2, a cross section of the concave surface 22a of the light emitting element mounting portion 22 is schematically shown, and only five light emitting elements 21 are shown. However, in practice, each light emitting element 21 is
Are arranged at predetermined intervals on the entire surface of the concave surface 22a.

Each light emitting element 21 is connected to a power source 23. The power supply 23 can cause each light emitting element 21 to emit light by supplying a drive current to each light emitting element 21. All of the excitation light emitted from each of the light emitting elements 21 enters the incident surface J of the light guide 15b within the range of the opening angle of the light guide 15b.

In the above configuration, an auto-fluorescent image of the subject can be obtained. In the present embodiment, the polychromator 6 is further used. That is, the endoscope system further includes the polychromator 6 and the personal computer 7 connected to the polychromator 6. The polychromator 6 has a light guide probe 6a, and can detect the intensity of light incident from the tip of the light guide probe 6a for each wavelength.

The light guide probe 6a is connected to the fiberscope 1
Is inserted through the forceps insertion port 14b, and is drawn through the inside of the fiber scope 1, and the tip of the fiber scope 1 comes out of the forceps port 14a. Then, the light guide probe 6 a guides the autofluorescence of the subject incident from the tip to the polychromator 6. The polychromator 6 detects the intensity of the autofluorescence for each wavelength, converts the intensity into a signal, and outputs the signal to the personal computer 7. After processing the received signal, the personal computer 7 displays on the monitor 7a a graph showing the intensity distribution of the autofluorescence for each wavelength.

The operation of the thus-configured fluorescence observation endoscope system according to this embodiment will be described below.
First, when an operator turns on a main power supply (not shown) of the fluorescence observation endoscope system, the power supply 23 of the light source device 2
1 is supplied with a drive current. Then, each light emitting element 21
Each emits excitation light. Each excitation light is supplied to the light guide 15b.
The excitation light is incident from the incident surface J within the range of the opening angle of, and all of these excitation lights are guided by the light guide 15b, emitted from the emission surface P, and further transmitted through the light distribution lens 15a.

In this state, the operator inserts the insertion section 11 of the fiberscope 1 into a body cavity of a living body. Then, the operator causes the distal end surface of the insertion section 11 to face the body cavity wall to be observed. Then, since the excitation light emitted from the light distribution lens 15a irradiates the body cavity wall, the tissue constituting the body cavity wall receives the excitation light and emits autofluorescence. The excitation light reflected by the autofluorescence and the body cavity wall enters the objective lens 16a. The objective lens 16a converges these lights on the distal end surface of the image guide 16b to form an image of the subject. The image guide 16b guides the auto-fluorescence and the excitation light and emits the light from the base end face. Eyepiece optical system 16
c causes the light emitted from the image guide 16b to enter the bandpass filter 31 of the imaging device 3.

Since the band-pass filter 31 blocks the excitation light of the incident light and transmits the auto-fluorescence, only the auto-fluorescence enters the image intensifier 33. Image intensifier 33
Amplifies and emits the incident autofluorescence. Then, the imaging optical system 34 converges the amplified light on the imaging surface of the camera head 35 to form an autofluorescent image of the subject. The camera head 35 converts the image on the imaging surface into a signal and sends the signal to the CCU 4. The CCU 4 generates a video signal based on the received signal, transmits the video signal to the monitor 5, and displays an autofluorescent image of the subject on the screen of the monitor 5.

The operator can know the state of the body cavity wall by observing the autofluorescence image displayed on the monitor 5. That is, if there is a site where the autofluorescence is weakened, the surgeon can determine that there is a high possibility that a lesion has occurred in the site. In addition, the surgeon can refer to the intensity distribution for each wavelength of the autofluorescence acquired by the polychromator 6 and displayed on the monitor 7a, and can use it for diagnosis.

As described above, since the light source device 2 in the fluorescence observation endoscope system according to the present embodiment has the light emitting element 21 that emits the excitation light as monochromatic light, the filter for blocking light in a band other than the excitation light is used. (A light source side band-pass filter or an infrared removing filter) or the like is unnecessary. Furthermore, since excitation light having excellent monochromaticity is obtained, there is no possibility that light in a band that hinders observation will be emitted from the light distribution lens 15a. Therefore, the operator can always observe a good autofluorescence image, and the accuracy of diagnosis is improved. In addition, since the light emitting element 21 is small, it is easy to reduce the size of the entire light source device 2.

Although the amount of light from one light emitting element 21 is limited, a sufficient amount of light can be obtained by simultaneously inputting light from a plurality of light emitting elements 21 to the light guide 15b. In addition, since all of the excitation light emitted from the light emitting element 21 enters the light guide 15b within the range of the opening angle of the light guide 15b, a necessary light amount can be efficiently obtained.

Further, the light emitting element 21 operates in a stable state immediately after the power is turned on. Therefore, the light source device 2 includes
Idling time is unnecessary. In addition, the preparation and maintenance effort is greatly reduced.

[Second Embodiment] The fluorescence observation endoscope system according to the present embodiment comprises an electronic endoscope 100, an external device 300 connected to the electronic endoscope 100, a light source device 2 'for excitation light, And a monitor 5. FIG. 3 is a schematic configuration diagram illustrating a fluorescence observation endoscope system according to the second embodiment.

First, the electronic endoscope 100 will be described. The electronic endoscope 100 includes an insertion section 101 inserted into a living body, an operation section 102 connected to the insertion section 101,
A connection unit 103 connected to the operation unit 102;
The insertion portion 101 has a flexible, substantially cylindrical shape, and the distal end side is sealed by a disk-shaped distal end surface. At least three through holes are opened in the distal end surface of the insertion portion 101, one of which is used as a forceps hole 104a, and the other two are respectively light distributions for normal illumination. The lens 105a and the observation objective lens 106a are fitted and sealed.

The operation section 102 has one end thereof inserted into the insertion section 101.
Is connected to the base end side. Various switches (not shown) for operating and setting the endoscope system are arranged on the surface of the operation unit 102. Further, a forceps insertion opening 104b is opened on a side surface near the distal end side of the operation unit 102. The forceps insertion opening 104b and the forceps hole 104a of the insertion portion 101 are connected by a forceps tube (not shown). Note that various instruments (forceps, treatment tools, probes, etc.) inserted from the forceps insertion port 104b are
The inside of the forceps tube is drawn through, and the tip of the tube extends out to the forceps hole 104a.

The connecting portion 103 is connected to the external device 300 and also connected to the operating portion 102 by a flexible connecting tube 103a. And the insertion part 10
A light guide / fiber bundle 105b (hereinafter abbreviated as a light guide) passes through the inside of the operation unit 102 and the connection unit 103. This ride guide 105b
Is composed of a large number of multimode optical fibers bundled densely, and both end surfaces thereof are formed as an incident surface through which light is incident and an exit surface through which light is emitted.

The light guide 105b has an exit surface facing the light distribution lens 105a, and an end on the incident surface side is led into the external device 300. In FIG. 3, this light guide 10
5b is schematically shown. That is, although the light guide 105b has a central portion shown by a single line, the light guide 105b actually has a uniform diameter over its entire length.

A band-pass filter 106b and an image sensor 106c are arranged near the distal end inside the insertion section 101 so as to face the objective lens 106a. A signal line 106 d extends through the insertion section 101, the operation section 102, and the connection section 103.
The signal line 106d is connected to the image pickup device 10 at one end.
6c, and the other end is connected to the external device 30.
It is drawn inside 0.

The band-pass filter 106b transmits the auto-fluorescence of the living body and cuts off the excitation light for exciting the auto-fluorescence. The image sensor 106c is a CCD
And converts the image formed on the imaging surface into an electric signal. The image sensor 106c is arranged so that its image plane substantially coincides with the image plane of the subject image formed by the objective lens 106a. Then, the image sensor 106c photoelectrically converts the image on the imaging surface within a predetermined imaging period, and outputs a signal obtained by the conversion to the signal line 106d within a subsequent transfer period. When the transfer period ends, the imaging period starts again. That is, in the imaging element 106c, the imaging period and the transfer period are alternately repeated.

Next, the external device 300 will be described.
The external device 300 includes a normal light source unit 31 for normal observation.
0, processor 320, system control unit 33
0, and the normal light source unit 310 and the processor 32
0, and a power supply 340 connected to the system control unit 330, respectively.

The normal light source section 310 has a white light source 311 for emitting white light. Further, the normal light source unit 310
Are, in order, on the optical path of the white light emitted from the white light source 311, the infrared cutoff filter 312 and the condenser lens 31.
3, a stop 314a and a rotary filter 315a.
The infrared cutoff filter 312 can remove infrared rays in the white light emitted from the white light source 311 to prevent heat radiation. The condenser lens 313 includes the infrared cutoff filter 3
The light emitted from 11 is converged on the incident surface of light guide 105b.

The stop 314a and the rotary filter 3
15a is a condenser lens 313 and a light guide 105b.
Are arranged in the optical path between the light incident surfaces. The aperture 31
4a is connected to the aperture control mechanism 314b. The aperture control mechanism 314b can adjust the amount of light by controlling the aperture 314a.

The rotary filter 315a has a disk-like outer shape, and is formed of RGB (red, green, and red) formed in an equiangular fan shape.
Blue) It has three color filters. The area between the color filters is formed as an opaque light shielding portion. This rotary filter 315a is connected to a filter drive motor 315b. Then, the filter driving motor 315b rotates each of the RGB color filters from “B” to “R” by rotating the rotation filter 315a.
They can be inserted into the optical path in the order of “G” → “R”. Further, the filter driving motor 315b can fix the rotary filter 315a in a state where the light shielding portion is inserted in the optical path.

The processor 320 includes a first stage signal processing circuit 3
21, control circuit 322, and video signal processing circuit 323
Having. The first-stage signal processing circuit 321 is connected to the signal line 106
It is connected to the image sensor 106c via d, and can receive and hold a signal transmitted from the image sensor 106c at a predetermined timing. Further, the first-stage signal processing circuit 321 performs processing such as amplification, white balance adjustment, γ correction, and A / D conversion on the held signal, and transmits the processed signal to the control circuit 322.

The control circuit 322 has an RGB memory and a timing controller (not shown). The RGB memory of the control circuit 322 is divided into a B area, a G area, and an R area. The RGB memory can store data corresponding to one screen of the monitor 5 for each of B, G, and R components. The timing controller of the control circuit 322 is for generating various reference signals, and various processes in the processor 320 proceed according to the reference signals. The control circuit 322
Writes the signal output from the first-stage signal processing circuit 321 into the RGB memory at a predetermined timing according to the reference signal output from the timing controller.

The video signal processing circuit 323 is connected to the monitor 5 and acquires data in the RGB memory in the control circuit 322 at a predetermined timing. Then, the video signal processing circuit 323 performs
It performs D / A conversion, encoding of a predetermined TV system, and the like, and converts it into a signal for screen display. The monitor 5 receives the converted signal and displays it on the screen according to a predetermined TV system.

Further, the processor 320 has a first driver circuit 324 connected to the control circuit 322. This driver circuit 324 is connected to the filter drive motor 315b of the normal light source section 310. Then, the control circuit 322 controls the filter drive motor 315b via the driver circuit 324 to rotate the rotary filter 315a at a predetermined speed.
The control circuit 322 is connected to the aperture control mechanism 314b of the normal light source unit 310. Then, the control circuit 32
Reference numeral 2 controls the aperture 314a via the aperture control mechanism 314b to adjust the light amount.

The system control unit 330 is connected to the first stage signal processing circuit 32 of the processor 320 via a signal line.
1, the control circuit 322, and the video signal processing circuit 323,
Each is connected. Furthermore, the system control unit 3
Reference numeral 30 is connected to the operation unit 102 of the electronic endoscope 100 and the light source device 2 ′ via a signal line (not shown), and controls the entire endoscope system.

Next, the light source device 2 'for excitation light will be described. The light source device 2 ′ includes the light emitting element 21, the light emitting element mounting part 22,
And a power supply 23. Further, the light source device 2 ′ of the present embodiment includes a rotary shutter 25a, a shutter drive motor 25b, a second driver circuit 25c, and a light guide probe 26.

The light guide probe 26 has a long and thin flexible tube and a fiber bundle disposed in the thin tube. The fiber bundle of the light guide probe 26 is configured by densely bundling a number of multimode optical fibers. The light guide probe 26 has one end surface formed as an incident surface on which light enters, and the other end surface formed as an exit surface for emitting light. In FIG. 3, the light guide probe 2
6 is schematically shown. That is, the light guide probe 2
6 has a central portion shown by a single line, but actually has a uniform diameter over its entire length.

The end of the light guide probe 26 on the incident surface side is drawn into the light source device 2 '. In addition,
The light guide probe 26 is disposed at a position where the incident surface corresponds to the incident surface of the light guide 15b in the first embodiment. Also, this light guide probe 26
The end on the emission surface side is drawn through the forceps insertion port 104b into the electronic endoscope 100 and protrudes outward at the forceps port 104a.

The outer shape of the rotary shutter 25a is a disk, and an opening (not shown) is opened in a part of the disk. The rotary shutter 25a is provided with the light emitting element 2
1 and rotatably disposed in the optical path between the light incident surfaces of the light guide probe 26. And this rotary shutter 2
When the opening 5a is located in the optical path, the excitation light emitted from the light emitting element 21 can pass through this opening and enter the incident surface of the light guide probe 26. However, when a portion other than the opening of the rotary shutter 25a is located in the optical path, the excitation light emitted from the light emitting element 21 is shielded by the rotary shutter 25a.

The rotary shutter 25a is attached to a shutter drive motor 25b. The shutter drive motor 25b is connected to a driver circuit 25c via a signal line. The driver circuit 25c includes:
By controlling the shutter drive motor 25b, the rotary shutter 25a can be rotated at a predetermined speed. By rotating, the rotary shutter 25 a can intermittently emit the excitation light emitted from the light emitting element 21 to the incident surface of the light guide probe 26. Note that, without providing the rotary shutter 25a,
However, the light emitting element 21 may be directly turned on / off.

The driver circuit 25c is connected to the driver circuit 324 of the processor 320 via a signal line. Therefore, the control circuit 322 of the processor 320
Can control the driver circuit 25c of the light source device 2 'via the driver circuit 324.

The operation of the fluorescence observation endoscope system of the present embodiment configured as described above will be described below.
First, when an operator turns on a main power supply (not shown) of the fluorescence observation endoscope system, the power supply 340 in the normal light source unit 310 of the external device 300 supplies a current to the white light source 311 to emit white light. Further, the driver circuit 324 controls the filter drive motor 315b to control the rotation filter 315.
a is rotated at a constant speed. In the initial state, the light emitting element 21 of the light source device 2 'is off, and the rotary shutter 25a is not rotating.

The white light emitted from the white light source 311 is
The infrared rays are removed by the infrared cutoff filter 312, the light amount is adjusted by the aperture 314a, and the light is directed to the rotary filter 315a. The rotating filter 315a converts the incident white light into B light, G light, and R light by sequentially inserting the color filters into the optical path. These B
The light, the G light, and the R light sequentially converge on the incident surface of the light guide 105b. Then, the light guided inside the light guide 105b is emitted from the emission surface of the light guide 105b, and further diverged through the light distribution lens 105a.

The processor 320 of the external device 300
Is synchronized with the driver circuit 324 in accordance with the imaging period and the transfer period of the image sensor 106c of the electronic endoscope 100. That is,
A predetermined period of time during which the B light is emitted from the light distribution lens 105a corresponds to an imaging period of the image sensor 106c, and the transfer period of the image sensor 106c ends before the next G light is emitted. . Then, the driver circuit 324 regulates the rotation speed of the rotary filter 315a via the filter drive motor 315b so that the same processing is performed when emitting G light or R light.

In this state, the operator operates the electronic endoscope 1
The insertion section 101 is inserted into the body cavity of the patient, and the distal end surface of the insertion section 101 is opposed to the body cavity wall to be observed.
Then, the B light, G emitted from the light distribution lens 105a
The light and the R light sequentially irradiate the body cavity wall. Then, these lights reflected by the body cavity wall are collected by the objective lens 106a and transmitted through the band-pass filter 106b,
The light is converged on the imaging surface of the imaging element 106c. Therefore, the light distribution lens 10 is provided on the imaging surface of the imaging element 106c.
An image of the subject when the B light is emitted from 5a, an image of the subject when the G light is emitted, and an image of the subject when the R light is emitted are sequentially formed. The image sensor 106c photoelectrically converts these images during the imaging period, and transmits the images to the signal line 106d during the transfer period.

The first-stage signal processing circuit 321 in the processor 320 of the external device 300 receives a signal from the image sensor 106c via the signal line 106d. Then, the first-stage signal processing circuit 321 amplifies,
Other signal processing and A / D conversion are performed, and the control circuit 3
22 in the RGB memory. That is, the signal corresponding to the emission of the B light is stored in the B area of the RGB memory, the signal corresponding to the emission of the G light is stored in the G area of the RGB memory, and the signal corresponding to the emission of the R light is stored in the R area of the RGB memory. Is stored.

The video signal processing circuit 323 includes the control circuit 32
The data in the RGB memory No. 2 is acquired at a predetermined timing, D / A converted and encoded by the TV system, and displayed on the monitor 5 on the screen. The monitor 5 displays a color image (normal image) of the body cavity wall. The surgeon can usually observe the body cavity wall by looking at the monitor 5.

In this state, the surgeon can further perform fluorescence observation of the body cavity wall. That is, the surgeon presses a switch (not shown) provided on the operation unit 102 of the electronic endoscope 100 to designate switching from normal observation to fluorescence observation. System control unit 3 of external device 300
30 detects that the switch of the operation unit 102 has been pressed, and recognizes that the operator has designated the fluorescence observation. Then, the system control unit 330 fixes the rotary filter 315a via the driver circuit 324 and the filter drive motor 315b in a state where the light shielding portion is inserted in the optical path. Accordingly, the white light emitted from the white light source 311 is shielded by the light shielding portion of the rotary filter 315a, and does not enter the light guide 105b.

At the same time, the system control unit 330
Controls the power supply 23 of the light source device 2 ′ to turn on the light emitting element 21, and rotates the rotary shutter 25 a via the driver circuit 25 c and the shutter drive motor 25 b.

The processor 320 of the external device 300
Is synchronized with the driver circuit 25c of the light source device 2 'in accordance with the imaging period and the transfer period of the image sensor 106c of the electronic endoscope 100. That is, the driver circuit 25c sets the period in which the opening of the rotary shutter 25a is located in the optical path to correspond to the imaging period of the image sensor 106c, and the period in which the opening of the rotary shutter 25a is located outside the optical path. To correspond to the transfer period of the image sensor 106c,
Rotary shutter 2 via shutter drive motor 25b
5a is defined.

Therefore, the excitation light emitted from the light emitting element 21 intermittently enters the light incident surface of the light guide probe 26.
Then, the excitation light guided in the light guide probe 26 is emitted from the tip to the body cavity wall. For this reason, the body cavity wall
It is intermittently illuminated by the excitation light.

The body cavity wall emits autofluorescence when irradiated with the excitation light. The objective lens 106a collects the autofluorescence and the excitation light reflected on the body cavity wall. The bandpass filter 106b is connected to the objective lens 10
Of the light emitted from 6a, the excitation light is blocked and the auto-fluorescence is transmitted. The transmitted autofluorescence is converged on the imaging surface of the imaging element 106c, and an image is formed by the autofluorescence from the body cavity wall.

At this time, the image pickup device 106c is in the image pickup period, and photoelectrically converts the image formed on the image pickup surface. Then, when the transfer period starts after the imaging period ends, the rotary shutter 25a of the light source device 2 'shields the excitation light. Therefore, no excitation light is emitted from the light distribution lens 105a during the transfer period of the image sensor 106c. During this transfer period, the image sensor 106c transmits a signal based on the image of the autofluorescence to the signal line 106d.

The first-stage signal processing circuit 321 in the processor 320 of the external device 300 receives a signal from the image sensor 106c via the signal line 106d. Then, the first-stage signal processing circuit 321 amplifies,
Other signal processing and A / D conversion are performed. Further, the first-stage signal processing circuit 321 writes the data obtained by the conversion into the RGB memory of the control unit 322.

The video signal processing circuit 323 includes the control circuit 32
The data in the RGB memory No. 2 is acquired at a predetermined timing, D / A converted and encoded by the TV system, and displayed on the monitor 5 on the screen. The monitor 5 displays a monochrome image (autofluorescence image) of autofluorescence of the body cavity wall. The surgeon can usually observe the body cavity wall by looking at the monitor 5. Note that this fluorescent image may be an image that is colored according to the intensity of the autofluorescence or the like.

The operator can know the state of the body cavity wall by observing the autofluorescence image displayed on the monitor 5. That is, if there is a site where the autofluorescence is weakened, the surgeon can determine that there is a high possibility that a lesion has occurred in the site.

Further, the operator can return the endoscope system to the initial state by pressing a switch (not shown) of the operation unit 102 to perform normal observation. That is, when recognizing that the operator has designated normal observation, the system controller 330 rotates the rotary filter 315a at a constant speed via the driver circuit 324 and the filter drive motor 315b. At the same time, the system controller 330
Controls the power supply 23 of the light source device 2 ′ to turn off the light emitting element 21. In this way, the operator can switch between normal observation and fluorescence observation as needed.

[0089]

According to the light source device of the present invention configured as described above, light from a plurality of light emitting elements can be efficiently incident on the fiber bundle. Further, by using a plurality of light emitting elements, the light quantity as a whole can be increased. Further, according to the endoscope system of the present invention, it is possible to irradiate the subject with light having excellent monochromaticity. Therefore, the surgeon can observe the subject in a situation where there is no light in the wavelength band that would obstruct the observation.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a fluorescence observation endoscope system according to a first embodiment of the present invention.

FIG. 2 is a diagram schematically showing a configuration of a light source device according to the first embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a fluorescence observation endoscope system according to a second embodiment of the present invention.

FIG. 4 is a schematic configuration diagram of a conventional fluorescence observation endoscope system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fiberscope 15a Light distribution lens 15b Light guide / fiber bundle 16a Objective lens 2 Light source device 21 Light emitting element 22 Light emitting element mounting part 22a Concave surface 3 Imaging device 35 Camera head 5 Monitor 100 Electronic endoscope 2 'Light source device 26 Light guide probe 106a Objective lens 106c Image sensor 300 External device 320 Processor 330 System control unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) H04N 7/18 H04N 7/18 MF term (Reference) 2G043 AA06 CA05 EA01 FA09 GA06 GB10 GB11 HA05 KA05 KA09 LA01 MA01 2H040 BA01 CA04 CA09 CA13 DA51 GA01 GA02 4C061 AA00 BB02 CC07 DD00 FF46 GG01 NN01 QQ04 QQ07 WW17 5C054 AA01 CA04 CA06 CC05 CC07 EB05 EB07 ED13 GA04 GB01 HA12

Claims (10)

[Claims] 1. A light source device for causing light to enter a fiber bundle from an incident surface thereof, comprising: a plurality of light emitting elements capable of emitting directional light in a predetermined direction; The angle formed between the light beam emitted from each light-emitting element and the central axis near the end of the fiber bundle on the incident surface side is 1/1 / the opening angle of the fiber bundle. A light-emitting element mounting portion for arranging the respective light-emitting elements such that the number of light-emitting elements is 2 or less. 2. The light-emitting element mounting portion has a concave surface facing the incident surface of the fiber bundle, and each of the light-emitting elements is fixed on the concave surface of the light-emitting element mounting portion. The light source device according to claim 1, wherein 3. The light source device according to claim 1, wherein said light emitting element is a light emitting diode. 4. The light source device according to claim 1, wherein said light emitting element is a laser diode. 5. The light source device according to claim 1, wherein said light emitting element emits, as monochromatic light, excitation light for exciting auto-fluorescence of living tissue. 6. A light source device according to claim 1, further comprising: a fiber bundle for guiding light emitted from said light emitting element of said light source device; and light guided by said fiber bundle, An illumination optical system for emitting light to the subject, an objective optical system for converging light from the subject to form an image of the subject, and an image of the subject formed by the objective optical system An endoscope system comprising an imaging unit. 7. A light emitting element for emitting excitation light for exciting autofluorescence of living tissue as monochromatic light, an illumination optical system for emitting excitation light emitted from the light emitting element to a subject, and An endoscope system comprising: an objective optical system that forms an image of the subject by converging the light of the subject; and an imaging unit that captures an image of the subject formed by the objective optical system. 8. The endoscope system according to claim 7, wherein said light emitting element is a light emitting diode. 9. The endoscope system according to claim 7, wherein said light emitting element is a laser diode. 10. The endoscope system according to claim 6, further comprising a display unit for displaying the image of the subject acquired by the imaging unit.